7A, Planning Case 11-011 – Select Senior Living PUD & Plat

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Internal Circulation Aside from the one-way flow at the pick-up/drop-off drive, the other internal roadways will allow two- way traffic flow. Because the conceptual parcel has no direct access onto either Lexington Avenue or County Road E, cross access between the two parcels must be provided. The westerly drive extends to a parking area at the rear of the senior center parcel, and then turns easterly to access the parking area for the conceptual parcel. The parking area for the conceptual parcel also can be accessed via the easterly driveway onto County Road E. To model the distribution of the traffic generated by the senior center and various uses considered for the conceptual parcel, RLK looked at the trip distribution of the highest generating use being considered. Also, RLK had to determine the directional split of the traffic. For the senior center, it was assumed that 45% would use the easterly driveway, 45% would use the westerly driveway and 10% would use the pick-up/drop-off driveway. For the conceptual parcel, RLK assumed 80% would use the easterly driveway and 20% of the traffic would use the westerly driveway. Based on the trip generation calculations found in Table 2, RLK determined the heaviest trip generator for each time frame as the worst case scenario to be tested. The A.M. Peak Hour trip generation is heaviest with a fast-food restaurant with drive-thru on the conceptual parcel. The P.M. Peak Hour trip generation would be heaviest with a pharmacy with a drive-thru on the concept parcel. In this case, the trip generation for the P.M. Peak Hour exceeds that for the A.M. Peak Hour, thus the P.M. Peak Hour was considered the critical Build Condition for analysis. By applying the site trip distribution to the Existing P.M. Peak Hour traffic, as found in the Spack report, RLK was able to model the Build condition in the P.M. Peak Hour scenario. Levels of service were no worse than LOS-C for any of the study intersections. Delay and stacking distance did not appear to be significant at any of the driveways during the PM Peak th Hour. SimTraffic analyses showed a 95 Percentile Queue length of 67 feet (2-3 car lengths) at the easterly driveway, and the model showed the queue cleared rapidly as traffic entered County Road E. Alternate Pick-Up/Drop-Off Access RLK reviewed the possibility of reversing the direction of the pick-up/drop-off drive between the Eastern Driveway and the Central Driveway. Instead of an eastbound movement, RLK tested the operation of the driveway as a westbound only movement. While such an alignment does create a situation where northbound to westbound movements into the pick-up/drop-off driveway may be blocked by southbound traffic, there are so few vehicles attempting to make this movement (e.g., one or two senior center vans or occasional visitors per peak hour, etc.) that the chance of intersection gridlock is quite small. From a traffic engineering perspective, the City’s proposed alignment with the eastbound one-way flow of the pick-up/drop-off drive is conceptually better, but a westbound drive is unlikely to be an operational concern. Conclusion RLK has tested several scenarios of trip generation and traffic operation for the Select Senior Living site and the conceptual parcel to the east. It is out conclusion that the trip generation and traffic operation associated with these potential uses will operate the same, if not better than the previous use on the site Page 6 of 7 June 6, 2011 RLK Incorporated Co. Rd. E & Lexington Traffic Study 2011-052-M